This invention relates to vending machines, and more particularly, to a dispensing mechanism adapted for dispensing rectangular, parallelepiped or cube shaped paper cartons containing a beverage or other liquid.
Various types of dispensing mechanisms have been used depending on the types of food products or goods being vended. One known type of dispensing mechanism which is suitable for vending rectangular, parallelepiped or cube shaped paper cartons is shown by the copending U.S. patent application of A. Kurosawa et al. Ser. No. 559,468 filed on Dec. 8, 1983, now U.S. Pat. No. 4,542,834. This type of dispensing is explained with reference to FIGS. 1-3 on the drawings.
A dispensing mechanism unit 1 includes an article storage area 2 and dispensing mechanism 3. The article storage area 2 comprises vertically disposed left and right side plates 2a and 2b, upper plate 2c and back plate 2d. A front support plate 2e extends across the front lower portion of said plates 2a and 2b, and is connected to both side plates. A front opening 4 is formed between side plates 2a, 2b, upper plate 2c and support plate 2e to provide access for loading the articles into storage area 2. Storage area 2 has a bottom discharge opening 5 through which the articles are dispensed.
Dispensing mechanism 3 is disposed within article storage area 2 and comprises a pair of flappers 3a, a rotatable shaft 3b, an article holding mechanism 3c and driving mechanism 9 for rotating rotatable shaft 3b. A support shaft 6a is removably attached to support plate 2e and another support shaft 6b is removably attached to back plate 2d. Support shafts 6a and 6b are axially spaced from one another and extend along a common axis. Each flapper 3a is pivotably supported by both supporting shafts 6a and 6b. The pair of flappers 3a are disposed in discharge opening 5 of storage area 2 to control the discharge of articles through opening 5. Rotatable shaft 3b extends vertically through the center portion of storage area 2 to divide storage area 2 into two columns for stacking the articles. Thus, one flapper 3a is disposed in storage area 2 below each column of articles. The lower end portion of rotatable shaft 3b is rotatably supported by a support bracket 8 fixed to back plate 2d and the upper portion of rotatable shaft 3b is connected to the driving mechanism 9 mounted on upper plate 2c.
Rotatable shaft 3a carries an arc shaped control plate 7 at its lower end. Control plate 7 contacts the lower or underside surface of flappers 3a. Therefore, when control plate 7 is in contact with both flappers 3a, both flappers 3a are aligned to lie in a horizontal position and discharge of articles through opening 5 is blocked.
Article holding mechanism 3c is disposed in storage area 2 at a position adjacent its lower end portion, i.e., holding mechanism 3c is at least aligned with the articles S.sub.1 ', S.sub.2 ' which are stacked above the lowermost articles S.sub.1 and S.sub.2 on the upper surface of flappers 3a. Holding mechanism 3c comprises a pair of flappers 3c.sub.1 which are rotatably supported on back plate 2d and support plate 2e similar to the manner of mounting flappers 3a of the dispensing mechanism 3. An arm 3c.sub.2 is fixed on rotatable shaft 3b to control movement of flappers 3c.sub.1. In accordance with the rotation of arm 3c.sub.2, one or the other of flappers 3c.sub.1 is pushed outwardly and upwardly. At that time, as shown in FIG. 3, the outer surface of this flapper 3c.sub.1 acts as a holding member to press an article S1, against the inner surface of side plate 2a or 2b and hold the article in position while an article below the held article is discharged through opening 5.
In this type construction of a dispensing mechanism, since avoiding premature discharge of articles is achieved by the clamping the articles between the side plate of the dispensing mechanism and a holding member, it is possible for the side plates of the dispensing mechanism to be deformed outwardly. This possibility is increased depending on increasing article size and/or increasing the holding force applied by the holding member. If deformation of the side plates does occur, smooth article discharging operations are interfered with.
One solution to the above problem would be to increase the strength of side plates. However, this would increase the cost of the apparatus and increase the weight of the dispensing mechanism.